Preparation and electrocatalytic activity of nanocrystalline Ni-Mo-Co alloy electrode for hydrogen evolution

Ni-Mo-Co alloy electrodes were prepared by electrodeposition technique with citric acid as a complexing agent. The influence of the main technical parameters such as the concentration of CoSO4 7H2O, the current density and the bath temperature on the component content in the Ni-Mo-Co alloy electrode were investigated by electron dispersive spectrometer (EDS), the microstructure and surface morphology of Ni-Mo-Co alloy electrodes were characterized by employing X-ray diffractometer (XRD) and scanning electron microscope (SEM), and the electrocatalytic activity of Ni-Mo-Co alloy electrode for hydrogen evolution was investigated by the method of the cathode polarization curves. The results showed that the excellent Ni-Mo-Co alloy electrode with 41.39 wt% Ni, 53.82 wt% Mo and 4.79 wt% Co was obtained when the concentration of CoSO4 x 7H2O was 8 g/L, the current density was 12 A/dm2 and the bath temperature was 25 degrees C. The mircostructure of the Ni-Mo-Co alloy was nanocrystalline and the average grain size was about 25 nm by calculating using Scherrer Equation. The electrocatalytic activity of Ni-Mo-Co alloy electrode for hydrogen evolution was better than that of Ni-Mo alloy electrode.